Heterogeneous polynuclear complex for use in the chemical deposition of composite metal or metal compound thin films

ABSTRACT

A heterogeneous polynuclear complex for use as a raw material in the chemical deposition of composite metal or composite metal thin films with the below formula. In the formula, M 1  and M 2  are mutually different transition metals, x is an integer of 0 or more and 2 or less, y is in integer of 1 or more and 2 or less, z is an integer of 1 or more and 10 or less, R 1  to R 4  are each one of a hydrogen atom and an alkyl group with a carbon number of 1 or more and 5 or less, and R 5  is a hydrogen atom, a carbonyl, an alkyl group with a carbon number of 1 or more and 7 or less, an allyl group or an allyl derivative. The heterogeneous polynuclear complex allows a composite metal thin film or a composite metal compound thin film containing a plurality of metals to be formed from a single raw material.

TECHNICAL FIELD

The present invention relates to a chemical deposition raw materialincluding a heterogeneous polynuclear complex, which is used forproducing a composite metal thin film or a composite metal compound thinfilm including different kinds of metals by a chemical deposition methodsuch as a CVD method or an ALD method. Specifically, the presentinvention relates to a chemical deposition raw material which is capableof forming a thin film including a composite metal in one-time filmformation and which is capable of forming a film at low temperature(about 200° C.) while having moderate thermal stability.

BACKGROUND ART

In various kinds of devices such as semiconductors, various kinds ofmetal thin films are used for satisfying the required properties of thedevices. As a method for forming these metal thin films, a chemicaldeposition method such as a CVD method, which is capable of forming auniform and homogeneous film at a high film formation rate and inconformity with even a three-dimensional shape etc. of a device, isused.

As a metal complex that is a raw material in formation of a metal thinfilm by the chemical deposition method, a complex including a pluralityof ligands such as cyclopentadienyl with one metal as a central metal(nucleus) (hereinafter, referred to as a mononuclear complex) as shownin the following chemical formula 1 is known. A complex including aplurality of metals of the same kind as central metals (hereinafter,referred to as a homogeneous polynuclear complex) as shown in thefollowing chemical formula 2 is also known.

In formation of a metal thin film for use in a device such as asemiconductor by use of the above-mentioned mononuclear complex orhomogeneous polynuclear complex as a chemical deposition raw material, athin film including a plurality of kinds of metals is often applied. Ina device having a reduced size and weight, such as a semiconductor, aplurality of metal thin films are applied, and deposited for impartingvarious kinds of required properties, so that the device is densifiedand highly integrated while attaining required properties. For example,when copper is used as a wiring material of a semiconductor, a structureis used in which a thin film of MnO, MnSiO and the like as a barrierlayer for preventing diffusion of copper, and a thin film of rutheniumor the like as a base for introducing the barrier layer are depositedtogether.

As an example of forming a thin film including a plurality of metals asdescribed above, mention is made of Patent Document 1, Patent Document 2and so on. Patent Document 1 suggests that a plurality of mononuclearcomplexes etc. are provided, and metal thin films are sequentiallydeposited from the complexes to form a plurality of metal layers eachincluding a single metal. Patent Document 2 suggests that a plurality ofmononuclear complexes etc. are mixed beforehand, and dissolved oremulsified to obtain an inert liquid, and from the inert liquid, acomposite metal thin film containing a plurality of metals is formed.

RELATED ART DOCUMENT Patent Documents

-   Patent Document 1: JP 2011-1568 A-   Patent Document 2: JP 2002-60944 A

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

However, when a plurality of thin films are sequentially formed by useof a plurality of complexes as in Patent Document 1, a large number ofsteps are required for film formation, condition setting is complicated,much time and labor is needed for quality control of raw materials, anduse of a plurality of raw materials causes an increase in cost. When aplurality of metal complexes are mixed beforehand as in Patent Document2, the complexes have different vaporization properties, and thereforethe ratio of metals in the thin film easily varies, so that formation ofa homogeneous film becomes difficult. Before film formation, rawmaterials may react with each other, leading to degeneration.

The present invention has been made in view of the background describedabove, and provides a chemical deposition raw material which is capableof forming a plurality of kinds of metal thin films in a simple process,and capable of forming a homogeneous thin film, and is easilyquality-controlled.

Means for Solving the Problems

As a solution to the problems described above, the present inventorsconducted the following studies for synthesizing a complex including aplurality of kinds of metals as central metals in one complex(hereinafter, referred to as a heterogeneous polynuclear complex), andapplying the complex as a chemical deposition raw material instead ofapplying a plurality of complexes having different metal species as in aconventional art.

When a heterogeneous polynuclear complex is applied as a chemicaldeposition raw material, first a plurality of kinds of metals as centralmetals should be all deposited in formation of a metal thin film by achemical deposition method as a required property of the chemicaldeposition raw material. Preferably, the deposition ratios of aplurality of metals are almost the same. The chemical deposition rawmaterial should also have such a general required property of a chemicaldeposition raw material that in formation of a thin film by a chemicaldeposition method, the chemical deposition raw material has thermalstability sufficient to prevent thermal decomposition in a vaporizationstage while having a decomposition property which ensures that a filmcan be formed at low temperature. The present inventors extensivelyconducted studies on a complex having all the above-mentionedproperties, and resultantly arrived at a chemical deposition rawmaterial of the present invention which includes a heterogeneouspolynuclear complex having a configuration as described below.

The present invention relates to a chemical deposition raw material forproducing a composite metal thin film or a composite metal compound thinfilm by a chemical deposition method, including a heterogeneouspolynuclear complex in which at least a diimine (L) containing twoimines and a carbonyl are coordinated to a first transition metal (M₁)and a second transition metal (M₂) as central metals, the heterogeneouspolynuclear complex being represented by the following formula:

wherein M₁ and M₂ are mutually different transition metals; x is aninteger of 0 or more and 2 or less, y is an integer of 1 or more and 2or less, and z is an integer of 1 or more and 10 or less; R₁ to R₄ areeach one of a hydrogen atom and an alkyl group with a carbon number of 1or more and 5 or less; and R₅ is a hydrogen atom, a carbonyl, an alkylgroup with a carbon number of 1 or more and 7 or less, an allyl group oran allyl derivative.

As described above, the complex in the present invention is aheterogeneous polynuclear complex including a plurality of kinds oftransition metals: a first transition metal (M₁) and a second transitionmetal (M₂) as central metals of the complex, and to these central metalsare coordinated at least a diimine (L) and a carbonyl (—CO) as ligands.When a thin film is formed from the complex by a chemical depositionmethod, a plurality of metals as central metals are all deposited.

The complex of the present invention has moderate thermal stabilitybecause the diimine as a ligand has a relatively strong bonding forcewith a transition metal, and the carbonyl as a ligand has a relativelyweak bonding forth with a transition metal. Since the carbon number ofthe alkyl group as each of substituents R₁ to R₅ is arbitrarilydesigned, the vapor pressure and the melting point can be adjusted.

Hereinafter, the heterogeneous polynuclear complex included in thechemical deposition raw material according to the present invention willbe described in detail.

First, x, y and z representing the numbers of ligands (R₅), diimines (L)and carbonyls (CO), respectively, in the raw material of the presentinvention will be described. x is an integer of 0 or more and 2 or less,y is an integer of 1 or more and 2 or less, and z is an integer of 1 ormore and 10 or less; Preferably, x is 1 or more and 2 or less, y is 1 ormore and 2 or less, and z is 3 or more and 8 or less.

Preferred ranges of the integers that can be selected as x, y and zdepend on the kind (valence) of the transition metal and the correlationassociated with the value of x. For example, provided that at least oneof M₁ and M₂ is Fe or Ru, preferably, y is 2 and z is 4 to 6 when x is0, preferably, y is 1 and z is 4 to 7 when x is 1, and preferably, y is1 and z is 2 to 6 when x is 2.

It is especially preferable that x is 1, y is 1 and z is n+2 as acombination of x, y and z, and mention is made of, for example, achemical deposition raw material including a heterogeneous polynuclearcomplex represented by the following formula:

wherein M₁ and M₂ are mutually different transition metals; n is 3 ormore and 6 or less; Each of R₁ and R₄ is an alkyl group with a carbonnumber of 1 or more and 4 or less, and each of R₂ and R₃ is a hydrogenatom, or an alkyl group with a carbon number of 1 or more and 3 or less;and R₅ is a carbonyl, or an alkyl group with a carbon number of 1 ormore and 4 or less.

M₁ and M₂ are mutually different transition metals. Examples of thetransition metal include titanium (Ti), vanadium (V), chromium (Cr),manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu),niobium (Nb), molybdenum (Mo), ruthenium (Ru), rhodium (Rh), palladium(Pd), silver (Ag), tantalum (Ta), tungsten (W), rhenium (Re), osmium(Os), iridium (Ir), platinum (Pt) and gold (Au). As the transitionmetal, Mn, Fe, Co, Ni, Cu, Nb, Mo, Ru, Rh, Ta, W, Ir and Pt arepreferable, and Mn, Fe, Co, Ni, Cu, Mo, Ru, W and Pt are especiallypreferable. As the transition metal as M₁, Ru, Mn and Fe are especiallypreferable, and as the transition metal as M₂, Mn, Fe, Co and Ni areespecially preferable.

Ligands to be coordinated to central metals will now be described. Inthe raw material of the present invention, at least a diimine and acarbonyl are coordinated to central metals including two transitionmetals as in, for example, the following compound. The present inventorsarrived at the raw material based on the following grounds regarding theconfigurations of the central metals and the ligands coordinated to thecentral metals.

The “diimine (L)” as a ligand refers to a ligand which has a secondaryamine (imino group) having a carbon-nitrogen double bond, and includes aconjugated diene including two conjugated double bonds as carbon-carbonbonds. A ligand having two secondary amines as described above tends toimprove thermal stability of the complex because nitrogen atoms in twoimino groups are strongly bonded to central metals. A diimine compoundtends to have a small molecular weight and a low boiling point, iseasily evaporated after decomposition, and thus hardly remains as animpurity in a metal film, and in addition to this advantage, the diiminecompound can increase the vapor pressure of a complex having the diiminecompound as a ligand.

Comparison between the ligands for ease of separation from the centralmetal shows that the carbonyl (—CO) tends to be more easily separatedfrom the central metal than the diimine (L). Here, when a compositemetal thin film is formed by a chemical deposition method, the amount ofeach transition metal deposited in the thin film often depends on thekind of a ligand coordinated to each transition metal. Of two transitionmetals, a transition metal having a larger amount of the carbonyl and asmaller amount of the diimine in terms of a ligand tends to be depositedin a larger amount in the formed composite metal thin film. For example,in the case of the following compound that is mentioned as a preferredexample in the present invention, the second transition metal M₂ towhich only the carbonyl is coordinated is apt to be deposited in alarger amount in the composite metal thin film than the first transitionmetal M₁ to which the diimine is coordinated.

wherein M₁ and M₂ are mutually different transition metals; n is 3 ormore and 6 or less; Each of R₁ and R₄ is an alkyl group with a carbonnumber of 1 or more and 4 or less, and each of R₂ and R₃ is a hydrogenatom, or an alkyl group with a carbon number of 1 or more and 3 or less;and R₅ is a carbonyl, or an alkyl group with a carbon number of 1 ormore and 4 or less.

Substituents R₁ to R₄ of the diimine will now be described. R₁ to R₄ areeach one of a hydrogen atom and an alkyl group with a carbon number of 1or more and 5 or less; and When the carbon chain is excessively long,the vapor pressure of the complex tends to decrease, and in the case ofa long-chain alkyl group with a carbon number of more than 5, thecomplex is difficult to vaporize. Either a linear or branched alkylgroup can be applied as each of substituents R₁ to R₄. For example, whena propyl group or a butyl group is applied, a n-propyl group, aniso-propyl group, a n-butyl group, an iso-butyl group, a sec-butylgroup, a tert-butyl group or the like can be applied.

With regard to each substituent, each of R₁ and R₄ is preferably analkyl group with a carbon number of 1 or more and 4 or less, especiallypreferably one of an ethyl group, a propyl group and a butyl group. Eachof alkyl groups of R₁ and R₄ is preferably a branched alkyl group,especially preferably one of an iso (i-)propyl group, a tert-butyl groupand a sec-butyl group. Each of R₂ and R₃ is preferably a hydrogen atomor an alkyl group with a carbon number of 1 or more and 3 or less,especially preferably one of a hydrogen atom, a methyl group and anethyl group.

The number of ligands R₅ is 0 or more and 2 or less, and preferably, oneof the ligands R₅ is a ligand of M₁. R₅ is one of a hydrogen atom, acarbonyl, an alkyl with a carbon number of 1 or more and 7 or less, anallyl or an allyl derivative, preferably a carbonyl or an alkyl with acarbon number of 1 or more and 4 or less, especially preferably acarbonyl, methyl ethyl or propyl. Which of a carbonyl and an alkyl ispreferred as the ligand R₅ depends on the kind of the first transitionmetal (M₁). A carbonyl is especially preferable when M₁ is Mn, Co, Rh,Re or Ir, and an alkyl is especially preferable when M₁ is Fe, Ru or Os.When the ligand R₅ is an alkyl, either a linear or branched alkyl can beapplied.

In the complex in the present invention, the total number of carbonyls(CO) is 1 or more and 10 or less, and preferably, the ligand of thefirst transition metal (M₁) has two or three carbonyls. The coordinationnumber (n) of carbonyls as the ligand of the second transition metal(M₂) is preferably 4 or 5, and which coordination number is preferreddepends on the kind of the second transition metal (M₂). Thecoordination number (n) is especially preferably 5 when M₂ is Mn or Re,and the coordination number (n) is especially preferably 4 when M₂ isCo, Rh or Ir.

Specific kinds of heterogeneous polynuclear complexes that are preferredfor the chemical deposition raw material of the present invention arelisted below as examples.

The chemical deposition raw material of the present invention describedabove can be produced in the following manner: a starting raw materialthat is a diazabutadiene derivative with the first transition metal (M₁)as a central metal is reacted with a complex to which a plurality ofcarbonyls are coordinated with the second transition metal (M₂) as acentral metal.

The present chemical deposition raw material is useful for formation ofa composite metal thin film by a CVD method. This thin film formationmethod includes preparing a reaction gas by vaporizing a raw materialincluding a heterogeneous polynuclear complex, introducing the reactiongas to a substrate surface, and decomposing the complex to deposit aplurality of metals. In this method, the heterogeneous polynuclearcomplex according to the present invention is used as a raw material.

The reaction atmosphere during formation of the thin film is preferablya reducing atmosphere, and therefore preferably, hydrogen or ammonia isintroduced as a reaction gas. The heating temperature during filmformation is preferably 150° C. to 350° C. When the heating temperatureis lower than 150° C., the film formation hardly proceeds, and thus arequired thickness is hard to obtain. When the heating temperature ishigher than 350° C., formation of a uniform thin film is difficult.

Advantageous Effects of the Invention

With the chemical deposition raw material according to the presentinvention, a composite metal thin film or a composite metal compoundthin film containing a plurality of metals can be formed from a singleraw material as described above. The raw material of the presentinvention has a high vapor pressure, is capable of producing a thin filmat low temperature, has moderate thermal stability, and is thus suitablefor film formation by a chemical deposition method.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a TG curve of a metal complex produced in anembodiment.

FIG. 2 shows a photograph of a cross-section of a metal thin film formedin an embodiment.

FIG. 3 illustrates a Ru/Mn ratio in a metal thin film formed in anembodiment.

DESCRIPTION OF EMBODIMENT

Hereinafter, the best embodiments in the present invention will bedescribed.

In the embodiments, the following four kinds of complexes weresynthesized. Synthesized complexes were each evaluated for physicalproperties, and subjected to a film formation test as a chemicaldeposition raw material.

EXAMPLE 1

A heterogeneous polynuclear complex(pentacarbonyl[dicarbonyl(N,N′-diisopropyl-1,4-diazabutadiene)methylruthenium]manganese(Mn—Ru)) having ruthenium as a first transition metal and manganese as asecond transition metal was produced. The synthesis reaction formula isas described below. Hereinafter, the production process will bedescribed in detail.

1.95 g (5 mmol) of decacarbonyldimanganese and 0.23 g (10 mmol) of metalsodium were added in a flask containing 250 ml of tetrahydrofuran. Thesolution was stirred at room temperature for 24 hours, a solutionobtained by dissolving 4.39 g (10 mmol) ofdicarbonyliodo(N,N′-diisopropyl-1,4-diazabutadiene)methylruthenium in250 ml of tetrahydrofuran was then added, and the mixture was stirred atroom temperature for 4 hours. After completion of the reaction, thereaction product was concentrated to obtain a muddy reaction mixture.The reaction mixture was extracted with hexane, and purified by columnchromatography with alumina as a carrier and hexane as an eluent.Sublimation purification was performed to obtain 3.30 g (6.5 mmol) ofpentacarbonyl[dicarbonyl(N,N′-diisopropyl-1,4-diazabutadiene)methylruthenium]manganese(Mn—Ru) as a specified substance (yield: 65%).

EXAMPLE 2

A heterogeneous polynuclear complex(tricarbonyl(N,N′-diisopropyl-1,4-diazabutadiene)(tetracarbonylcobalt)manganese (Co—Mn)) having manganese as a first transition metal and cobalt as asecond transition metal was produced. The synthesis reaction formula isas described below. Hereinafter, the production process will bedescribed in detail.

1.71 g (5 mmol) of octacarbonyldicobalt and 0.23 g (10 mmol) of metalsodium were added in a flask containing 250 ml of tetrahydrofuran. Thesolution was stirred at room temperature for 24 hours, a solutionobtained by dissolving 3.60 g (10 mmol) ofbromotricarbonyl(N,N′-diisopropyl-1,4-diazabutadiene)manganese in 250 mlof tetrahydrofuran was then added, and the mixture was stirred at roomtemperature for 4 hours. After completion of the reaction, the reactionproduct was concentrated, and then extracted with hexane. Afterrecrystallization from hexane at −30° C., sublimation purification wasperformed to obtain 1.13 g (5.0 mmol) oftricarbonyl(N,N′-diisopropyl-1,4-diazabutadiene)(tetracarbonylcobalt)manganese (Co—Mn) as a specified substance (yield: 50%).

EXAMPLE 3

A heterogeneous polynuclear complex(dicarbonyl(N,N′-diisopropyl-1,4-diazabutadiene)(tetracarbonylcobalt)methylruthenium(Co—Ru)) having ruthenium as a first transition metal and cobalt as asecond transition metal was produced. The synthesis reaction formula isas described below. Hereinafter, the production process will bedescribed in detail.

1.71 g (5 mmol) of octacarbonyldicobalt and 0.23 g (10 mmol) of metalsodium were added in a flask containing 250 ml of tetrahydrofuran. Thesolution was stirred at room temperature for 24 hours, a solutionobtained by dissolving 4.39 g (10 mmol) ofdicarbonyliodo(N,N′-diisopropyl-1,4-diazabutadiene)methylruthenium in250 ml of tetrahydrofuran was then added, and the mixture was stirred atroom temperature for 4 hours. After completion of the reaction, thereaction product was concentrated to obtain a muddy reaction mixture.The reaction mixture was extracted with hexane, and purified by columnchromatography with alumina as a carrier and hexane as an eluent.Sublimation purification was performed to obtain 2.42 g (5.0 mmol) ofdicarbonyl(N,N′-diisopropyl-1,4-diazabutadiene)(tetracarbonylcobalt)methylruthenium(Co—Ru) as a specified substance (yield: 50%).

EXAMPLE 4

A heterogeneous polynuclear complex (pentacarbonyl[dicarbonyl(ethyl)(N,N′-diisopropyl-1,4-diazabutadiene)ruthenium]manganese (Mn—Ru)) havingruthenium as a first transition metal and manganese as a secondtransition metal was produced. The synthesis reaction formula is asdescribed below. Hereinafter, the production process will be describedin detail.

1.95 g (5 mmol) of decacarbonyldimanganese and 0.23 g (10 mmol) of metalsodium were added in a flask containing 250 ml of tetrahydrofuran. Thesolution was stirred at room temperature for 24 hours, a solutionobtained by dissolving 4.53 g (10 mmol) ofdicarbonylethyliodo(N,N′-diisopropyl-1,4-diazabutadiene)ruthenium in 250ml of tetrahydrofuran was then added, and the mixture was stirred atroom temperature for 4 hours. After completion of the reaction, thereaction product was concentrated to obtain a muddy reaction mixture.The reaction mixture was extracted with hexane, and purified by columnchromatography with alumina as a carrier and hexane as an eluent.Sublimation purification was performed to obtain 2.98 g (5.7 mmol) ofpentacarbonyl[dicarbonyl(ethyl)(N,N′-diisopropyl-1,4-diazabutadiene)ruthenium]manganese(Mn—Ru) as a specified substance (yield: 57%).

Evaluation of physical properties of heterogeneous polynuclear complex:Physical properties were evaluated by TG for the heterogeneouspolynuclear complexes produced in Examples 1 and 4. Analysis wasperformed by observing a change in weight of a complex sample (5 mg) inheating of the sample at a temperature elevation rate of 5° C./min overa measurement temperature range, i.e. from room temperature to 450° C.,under a nitrogen atmosphere in TG-DTA2000SA manufactured by BRUKERCorporation. For Example 1, analysis (TG measurement under reducedpressure) with a complex sample heated at a pressure of 5 Torr wasperformed. The results are shown in FIG. 1.

FIG. 1 shows that the complexes in Examples 1 and 4 were vaporized anddecomposed by heating at about 130° C., and thus these complexes had alow decomposition temperature, and were capable of forming a film at lowtemperature. The results of the TG measurement under reduced pressureshowed that the complex in Example 1 was totally vaporized without beingdecomposed at a pressure during film formation.

Film formation test: Next, a film formation test was conducted in whicha composite metal thin film was formed by a CVD method with the complexproduced in Example 1 as a raw material compound.

The metal thin film was formed on a substrate (15 mm×15 mm) with asilicon oxide film deposited on a silicon substrate by use oftetraethoxysilane (TEOS). As a film formation apparatus, a hot wall typethermal CVD apparatus was used. A reaction gas (hydrogen) was fed at aconstant flow rate by use of a mass flow controller. Film formationconditions are as described below. The result of observing across-section of the metal thin film with a SEM is shown in FIG. 2.

Substrate: SiO₂

Film formation temperature: 250° C.

Sample temperature: 100° C.

Film formation pressure: 5 torr

Reaction gas (hydrogen) flow rate: 10 sccm

Film formation time: 60 minutes

The metal thin film formed in this way was glossy pure white, and had athickness of 47.2 nm. FIG. 2 shows that the metal thin film formed onSiO₂ had a smooth and uniform surface.

M₁/M₂ ratio: the Ru/Mn ratio was analyzed as an abundance of metalelements by an X-ray photoelectron spectroscopy (XPS) method for themetal thin film formed as described above. As a measurement apparatus,KRATOS Axis Nova manufactured by Shimadzu Corporation was used. In thismeasurement, the thin film (thickness: 47.2 nm) was analyzed in a depthdirection from the vicinity of the surface to the upper side of thevicinity of the interface with the SiO₂ film. In the vicinity of theinterface with the SiO₂ film, actions of Si and O made it difficult tocorrectly analyze the Ru/Mn ratio, and the analysis was performed over arange where the impact was low. The results are shown in FIG. 3. Thehorizontal axis in FIG. 3 is approximately consistent with a thickness(47.2 nm) from the thin film surface to the upper side of the vicinityof the interface with the SiO₂ film.

FIG. 3 shows that both Ru and Mn were deposited in the metal thin film.The Ru/Mn ratio was almost constant (around 0.45) although it tended tobe slightly high in the vicinity of the surface of the thin film.

INDUSTRIAL APPLICABILITY

According to the present invention, a composite metal thin film can beformed from a single raw material by a chemical deposition method, andit is easy to make the thin film homogeneous and control quality of rawmaterials. Thus, the present invention can be applied to uses whichemploy a structure in which a plurality of metal layers are deposited,such as copper diffusion layers in semiconductor devices.

The invention claimed is:
 1. A chemical deposition raw material forproducing a composite metal thin film or a composite metal compound thinfilm by a chemical deposition method, comprising a heterogeneouspolynuclear complex in which as ligands, at least a diimine (L) and acarbonyl are coordinated to a first transition metal (M₁ ) and a secondtransition metal (M₂) as central metals, the heterogeneous polynuclearcomplex being represented by the following formula:

wherein M₁ and M₂ are different transition metals; x is an integer of 0or more and 2 or less, y is an integer of 1 or more and 2 or less, and zis an integer of 1 or more and 10 or less; R₁ to R₄ are each one of ahydrogen atom and an alkyl group with a carbon number of 1 or more and 5or less; and R₅ is a hydrogen atom, a carbonyl, an alkyl group with acarbon number of 1 or more and 7 or less, an allyl group or an allylderivative.
 2. The chemical deposition raw material according to claim1, wherein x is 1, y is 1 and z is n +2, where n is the number ofcarbonyl groups bound to second transition metal M₂, the chemicaldeposition raw material comprising a heterogeneous polynuclear complexrepresented by the following formula:

wherein M₁ and M₂ are different transition metals; n is 3 or more and 6or less; Each of R₁ and R₄ is an alkyl group with a carbon number of 1or more and 4 or less, and each of R₂ and R₃ is a hydrogen atom, or analkyl group with a carbon number of 1 or more and 3 or less; and R₅ is acarbonyl, or an alkyl group with a carbon number of 1 or more and 4 orless.
 3. The chemical deposition raw material according to claim 2,wherein each of R₁ and R₄ is one of an ethyl group, a propyl group and abutyl group.
 4. The chemical deposition raw material according to claim2, wherein each of R₂ and R₃ is one of a hydrogen atom, a methyl groupand an ethyl group.
 5. The chemical deposition raw material according toclaim 2, wherein R₅ is a carbonyl group, methyl group, ethyl group orpropyl group.
 6. A chemical deposition method of a composite metal thinfilm or a composite metal compound thin film, comprising preparing a rawmaterial gas by vaporizing a raw material defined in claim 2 including aheterogeneous polynuclear complex, and heating the raw material gaswhile introducing the raw material gas to a substrate surface to deposita composite metal thin film or a composite metal compound thin film. 7.The chemical deposition raw material according to claim 1, wherein thetransition metal is one of Mn, Fe, Co, Ni, Cu, Nb, Mo, Ru, Rh, Ta, W, Irand Pt.
 8. The chemical deposition raw material according to claim 7,wherein each of R₁ and R₄ is one of an ethyl group, a propyl group and abutyl group.
 9. The chemical deposition raw material according to claim7, wherein each of R₂ and R₃ is one of a hydrogen atom, a methyl groupand an ethyl group.
 10. The chemical deposition raw material accordingto claim 7, wherein R₅ is a carbonyl group, methyl group, ethyl group orpropyl group.
 11. A chemical deposition method of a composite metal thinfilm or a composite metal compound thin film, comprising preparing a rawmaterial gas by vaporizing a raw material defined in claim 7 including aheterogeneous polynuclear complex, and heating the raw material gaswhile introducing the raw material gas to a substrate surface to deposita composite metal thin film or a composite metal compound thin film. 12.The chemical deposition raw material according to claim 1, wherein M₁ isone of Ru, Mn and Fe, M₂ is one of Mn, Fe, Co and Ni, and M₁ and M₂ aredifferent.
 13. The chemical deposition raw material according to claim12, wherein each of R₁ and R₄ is one of an ethyl group, a propyl groupand a butyl group.
 14. The chemical deposition raw material according toclaim 12, wherein each of R₂ and R₃ is one of a hydrogen atom, a methylgroup and an ethyl group.
 15. A chemical deposition method of acomposite metal thin film or a composite metal compound thin film,comprising preparing a raw material gas by vaporizing a raw materialdefined in claim 12 including a heterogeneous polynuclear complex, andheating the raw material gas while introducing the raw material gas to asubstrate surface to deposit a composite metal thin film or a compositemetal compound thin film.
 16. The chemical deposition raw materialaccording to claim 1, wherein each of R₁ and R₄ is one of an ethylgroup, a propyl group and a butyl group.
 17. The chemical deposition rawmaterial according to claim 16, wherein each of R₂ and R₃ is one of ahydrogen atom, a methyl group and an ethyl group.
 18. The chemicaldeposition raw material according to claim 1, wherein each of R₂ and R₃is one of a hydrogen atom, a methyl group and an ethyl group.
 19. Thechemical deposition raw material according to claim 1, wherein R₅ is acarbonyl group, methyl group, ethyl group or propyl group.
 20. Achemical deposition method of a composite metal thin film or a compositemetal compound thin film, comprising preparing a raw material gas byvaporizing a raw material defined in claim 1 including a heterogeneouspolynuclear complex, and heating the raw material gas while introducingthe raw material gas to a substrate surface to deposit a composite metalthin film or a composite metal compound thin film.